1. Field of the Invention
The present invention concerns an inkjet printing system with at least one ink cartridge and an associated ink cartridge receptacle. The ink cartridge can be easily exchanged without an ink cartridge exchange device and is suitable for all inkjet printing devices, both those that operate with a moving inkjet print head and those with an unmoving inkjet print head during the printing.
2. Description of the Prior Art
The known inkjet printing systems differ in the means for generation of a relative movement between the print item and the inkjet print head. In contrast to conventional printers, in franking machines often only the inkjet print head together with its receptacle is moved, and the print item remains unmoving during the printing, or the print item is moved and the inkjet print head is stationary, i.e. remains unmoving in a printing position during the printing.
As used herein, a print item encompasses flat articles to be printed such as mail pieces, letter envelopes, postcards, chip cards, admission cards [tickets], bands and other substrates for printed information.
A secure printing apparatus with a removable print head is known from the European patent application EP 875 861 A2, with which printing apparatus a franking imprint is only possible when a hatch is closed. The latter can be opened only if the print head was shifted into a region adjacent to the printing position, i.e. when the printing module has arrived in an exchange position. The print head is integrated into an ink cartridge and installed in a printing module. The access to the ink cartridges of the printing module in the exchange position ensues from the outside via a flap whose position is interrogated by a microswitch. If the printing module is located in the exchange position, no access to the data lines is possible.
A secure printing apparatus with a removal print head is known from the European patent application EP 881 086 B1. This printing apparatus is equipped with: electrical connection means which establish a connection to the electrical contacts of the ink cartridges, wherein the later are installed at the printing module that was moved into the printing station; and with localization means to localize the printing module in a park (exchange) station in which the electrical connection means no longer engage with the electrical contacts, and wherein the printing module in the park (exchange) station can be removed by a user; as well as with insulation means to insulate the park (exchange) station from the electrical connection means.
An arrangement to exchange inkjet printing modules was proposed in the European patent application EP 1 880 857 A2, wherein two ink cartridges are designated with the last term, which two ink cartridges—in contrast to the solutions cited above—do not still need to be completed with an exchangeable printing module, in that they are arranged in an additional housing. Rather, the two ink cartridges are inserted directly into a receptacle of the pivot device. The latter is pivoted together with the inserted ink cartridges, whereby in contrast to the aforementioned solutions their print heads do not shift from the printing position into an exchange position but rather are pivoted. The exchange arrangement is used in the franking machine of the Centormail® type from the manufacturer Francotyp Postalia GmbH and has additional differences relative to the aforementioned solutions: in the exchange position, the electrical contracts are connected to the ink cartridges, and in the exchange position there are no means that detach the electrical contacts of the print head beforehand for removal of the ink cartridges or insulate the printing device in the park position before the ink cartridges are exchanged.
The arrangement has bars to lock the ink cartridges and, per ink cartridge, a draw hook mechanically connected with a return spring as well as a guide lever. This device for changing the ink cartridges that is attached to the ink cartridge receptacle is, on the one hand, materially intensive and can hardly satisfactorily solve a problem that is apparent using FIG. 9 of EP 1 880 857 A2: because the lower rear edge of the nozzle face rests on an elastic part which should prevent a contacting of the counterpart with the contact panel, the separation is small. Therefore, in the removal of the ink cartridge, the elastic parts and the contacts can nevertheless be contaminated by ink that has collected on the lower rear edge during the printing.